Liquid stable MDI prepolymers and liquid stable curative systems suitable for room temperature casting which yield high performance urethane elastomers

ABSTRACT

The invention relates to liquid stable MDI prepolymers and curative systems which are suitable for room temperature casting and which yield high performance low-shrinkage urethane elastomers upon room-temperature curing, the prepolymer and curative components, the elastomers themselves, and separately packaged prepolymer component and its complementary curative component provided as a single unit or kit.

The present application is a division of U.S. Ser. No. 09/593,913 filedon Jun. 14, 2000.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Liquid stable MDI prepolymers and liquid stable curative systemssuitable for room temperature casting which yield high performanceurethane elastomers.

2. Prior Art

A search of the prior art showed many prepolymers and many curatives,none of which were specifically adapted to room temperature casting forthe production of high-performance urethane elastomers, especially suchelastomers which have remarkable low-shrink characteristics, whereinboth the prepolymer and the curative are liquid or semi-liquid andstable at room temperature, and wherein the curing can also be effectedat room temperature, and much less with systems which are totally freeof TDI and which rely solely on MDI as the isocyanate-providingingredient of the prepolymer.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide liquid stable MDIprepolymers and liquid stable curative systems which are specificallyadapted for room temperature casting and which yield high performanceurethane elastomers upon room-temperature curing, the elastomer itself,as well as commercial combinations of the prepolymer and itscomplementary curative, separately packaged but together as a singleunit or kit. Other objects of the invention will become apparenthereinafter.

SUMMARY OF THE INVENTION

What we believe to be our invention, then, inter alia, comprises thefollowing, singly or in combination:

A room-temperature liquid stable prepolymer (P) which is the reactionproduct of

a) methylene diphenylisocyanate or a prepolymer of methylenediphenylisocyanate and an about 500-1000 equivalent weightpolytetramethylene ether glycol or polyoxypropylene/polyoxyethylene diolor triol having at least 21% residual NCO,

b) polytetramethylene ether glycol of about 500 to 1000 equivalentweight, and

c) a polyoxypropylene/polyoxyethylene triol or polyoxypropylene triol ofabout 1300 to 2000 equivalent weight,

the percentage by weight in the prepolymer (P) being about 32 to 72% of(a), about 52 to 22% of (b), and about 6 to 15% of (c), and thepercentage of residual NCO in the prepolymer (P) being about 6 to 18% byweight,

the prepolymer (P) having a viscosity at room temperature of about 1200to 26000 cps,

which prepolymer (P) is curable and castable at room temperature toyield a high-performance urethane elastomer;

such a prepolymer (P) wherein the percentage of residual NCO in theprepolymer(P) is about 11.5-13.5% by weight and wherein the prepolymer(P) has a room temperature viscosity of about 3500 to 5000 cps;

such a prepolymer (P) wherein a) is methylene diphenylisocyanate;

such a prepolymer (P) wherein c) is a polyoxypropylene/polyoxyethylenetriol having an equivalent weight of about 1300 to 2000 or apolyoxypropylene triol having an equivalent weight of about 1300 to2000;

such a prepolymer (P) wherein (a) is a liquid uretonimine-modifiedmethylene diphenylisocyanate;

such a prepolymer (P) wherein b) has an equivalent weight of about 500;

such a prepolymer (P) wherein b) has an equivalent weight of about 1000;

such a prepolymer (P) wherein a) is a previously-prepared reactionproduct of methylene diphenylisocyanate and polytetramethylene etherglycol having an equivalent weight of about 500 to 1000;

such a prepolymer (P) wherein a) is a previously-prepared reactionproduct of methylene diphenylisocyanate and apolyoxypropylene/polyoxyethylene diol having an equivalent weight ofabout 500 to 1000;

such a prepolymer (P) which is curable at room temperature with anapproximately stoichiometric equivalent of a liquid curative consistingessentially of the following components:

(1) a polyoxypropylene/-polyoxyethylene diol of about 1000 to 2000equivalent weight, (2) a polyoxypropylene/-polyoxyethylene triol ofabout 1300 to 2000 equivalent weight, (3) a chain extender having anquivalent weight of about 25 to 125, (4) a room-temperature liquidstable prepolymer (P) having a 6 to 18% residual NCO, (5) a diluent, (6)a degassing aid, and (7) a urethane catalyst, the relative amounts byweight being respectively 30-90%, 3-20%, 5-30%, 0-30%, 0-15%,0.001-0.05%, and 0.01-0.5%;

such a prepolymer (P) which is cured at room temperature with anapproximately stoichiometric equivalent of a liquid curative consistingessentially of the following components:

(1) a polyoxypropylene/-polyoxyethylene diol of about 1000 to 2000equivalent weight, (2) a polyoxypropylene/-polyoxyethylene triol ofabout 1300 to 2000 equivalent weight, (3) a chain extender having anequivalent weight of about 25 to 125, (4) a room-temperature liquidstable prepolymer (P) having a 6 to 18% residual NCO, (5) a diluent, (6)a degassing aid, and (7) a urethane catalyst, the relative amounts byweight being respectively 30-90%, 3-20%, 5-30%, 0-30%, 0-15%,0.001-0.05%, and 0.01-0.5%;

such a cured prepolymer wherein the amounts of (4) and (5) in thecurative are respectively 10-20 and 5-15% by weight;

such a prepolymer (P) which is curable at room temperature with anapproximately stoichiometric equivalent of a liquid curative consistingessentially of the following components:

(1) a polyoxypropylene/-polyoxyethylene diol of about 1000 to 2000equivalent weight, (2) a polyoxypropylene/-polyoxyethylene triol ofabout 1300 to 2000 equivalent weight, (3) a chain extender having anequivalent weight of about 25 to 125, (4) a room-temperature liquidstable prepolymer (P) having a 6 to 18% residual NCO, (5) a diluent, (6)a degassing aid, and (7) a urethane catalyst, the relative amounts byweight being respectively 30-90%, 3-20%, 5-30%, 0-30%, 0-15%,0.001-0.05%, and 0.01-0.5% to give a cured urethane elastomer having thefollowing properties after mixing and curing for seven days at roomtemperature:

Tensile strength (ASTM Method D-412) about 1300-2700 psi Elongation(ASTM Method D-412) about 250-700% Die C Tear (ASTM Method D-695) about140-400 pli Split Tear (ASTM Method D-1938) about 20-100 pli Rebound(ASTM Method D-2632) about 45-65% Shore A Hardness (ASTM Method D-2240)about 70-95 Gel time (25° C.) about 14-40 min.;

such a prepolymer (P) wherein the percentage of residual NCO in theprepolymer (P) is about 11.5-13.5% by weight and wherein the prepolymer(P) has a room temperature viscosity of about 3500 to 5000 cps and iscured at room temperature with an approximately stoichiometricequivalent of a liquid curative consisting essentially of the followingcomponents:

(1) a polyoxypropylene/-polyoxyethylene diol of about 1000 to 2000equivalent weight, (2) a polyoxypropylene/-polyoxyethylene triol ofabout 1300 to 2000 equivalent weight, (3) a chain extender having anequivalent weight of about 25 to 125, (4) a room-temperature liquidstable prepolymer (P) having a 6 to 18% residual NCO, (5) a diluent, (6)a degassing aid, and (7) a urethane catalyst, the relative amounts byweight being respectively 30-90%, 3-20%, 5-30%, 0-30%, 0-15%,0.001-0.05%, and 0.01-0.5% and a room-temperature viscosity of about300-50000 cps, to give a cured urethane elastomer having the followingproperties after mixing and curing for seven days at room temperature:

Tensile strength (ASTM Method D-412) about 1300-2700 psi Elongation(ASTM Method D-412) about 250-700% Die C Tear (ASTM Method D-695) about140-400 pli Split Tear (ASTM Method D-1938) about 20-100 pli Rebound(ASTM Method D-2632) about 45-65% Shore A Hardness (ASTM Method D-2240)about 70-95 Gel time (25° C.) about 14-40 min.;

such a cured prepolymer wherein the amounts of (4) and (5) in thecurative are respectively 10-20 and 5-15% by weight;

such a cured product wherein the prepolymer (P) is present in an up toabout 13% stoichiometric excess with respect to the curative;

such a cured product wherein the prepolymer (P) is present in about a 2to 7% stoichiometric excess with respect to the curative;

such a prepolymer (P) wherein the percentages by weight of a), b), andc) are respectively about 54%, about 36%, and about 10%;

such a prepolymer (P) cured with an approximately stoichiometricequivalent of a curative consisting essentially of (1) apolyoxypropylene/-polyoxyethylene diol of about 1000 to 2000 equivalentweight, (2) a polyoxypropylene/-polyoxyethylene triol of about 1300 to2000 equivalent weight, (3) a chain extender having an equivalent weightof about 25 to 125, (4) a room-temperature liquid stable prepolymer (P)having a 11.5 to 13.5% residual NCO, (5) a diluent, (6) a degassing aid,and (7) a urethane catalyst, the relative amounts by weight beingrespectively approximately 54%, 13%, 10%, 15%, 8%, 0.005% and 0.006%;

such a cured prepolymer (P) wherein the curative has a viscosity at roomtemperature of about 3000-5000 cps and a specific gravity of about1.05-1.08;

such a cured product wherein the prepolymer (P) is present in an up toabout 13% stoichiometric excess with respect to the curative;

such a cured product the prepolymer (P) is present in about a 2 to 7%stoichiometric excess with respect to the curative;

such a cured prepolymer (P) wherein the properties after mixing andcuring for seven days at room temperature are as follows:

Tensile strength (ASTM Method D-412) about 1550 psi Elongation (ASTMMethod D-412) about 500% Die C Tear (ASTM Method D-695) about 250 pliSplit Tear (ASTM Method D-1938) about 45 pli Rebound (ASTM MethodD-2632) about 55% Shore A Hardness (ASTM Method D-2240) about 80 Geltime (25° C.) about 20-30 min.;

such a cured prepolymer (P) wherein the degassing aid is a siliconeemulsion;

such a cured prepolymer (P) wherein the catalyst is a mixture oftriethylene diamine and 2,3-dimethyltetra-hydropyrimidine or bismuthneodecanoate;

such a cured prepolymer (P) wherein the degassing aid is a siliconeemulsion and the catalyst is a mixture of triethylene diamine and2,3-dimethyltetrahydro-pyrimidine or bismuth neodecanoate.

Moreover, a kit comprising the separately packaged prepolymer (P) and aseparately packaged curative consisting essentially of (1) apolyoxypropylene/-polyoxyethylene diol of about 1000 to 2000 equivalentweight, (2) a polyoxypropylene/-polyoxyethylene triol of about 1300 to2000 equivalent weight, (3) a chain extender having an equivalent weightof about 25 to 125, (4) a room-temperature liquid stable prepolymer (P)having a 6 to 18% residual NCO, (5) a diluent, (6) a degassing aid, and(7) a urethane catalyst, the relative amounts by weight beingrespectively 30-90%, 3-20%, 5-30%, 0-30%, 0-15%, 0.001-0.05%, and0.01-0.5%;

such a kit wherein the curative has a viscosity at room temperature ofabout 300-50000 cps and a specific gravity of about 1.02-1.15;

such a kit comprising the separately packaged prepolymer (P) wherein thepercentage of residual NCO in the prepolymer (P) is about 11.5-13.5% byweight and wherein the prepolymer (P) has a room temperature viscosityof about 3500 to 5000 cps and a separately packaged curative consistingessentially of (1) a polyoxypropylene/-polyoxyethylene diol of about1000 to 2000 equivalent weight, (2) a polyoxypropylene/-polyoxyethylenetriol of about 1300 to 2000 equivalent weight, (3) a chain extenderhaving an equivalent weight of about 25 to 125, (4) a room-temperatureliquid stable prepolymer (P) having a 6 to 18% residual NCO, (5) adiluent, (6) a degassing aid, and (7) a urethane catalyst, the relativeamounts by weight being respectively 30-90%, 3-20%, 5-30%, 0-30%, 0-15%,0.001-0.05%, and 0.01-0.5% and a room-temperature viscosity of about300-50000 cps;

such a kit wherein the amounts of (4) and (5) in the curative arerespectively 10-20 and 5-15% by weight;

such a kit wherein the curative consists essentially of the statedcomponents in the following approximate percentages: 54%, 13%, 10%, 15%,8%, 0.005%, and 0.006% and has a viscosity at room temperature of about3000 to 5000 cps and a specific gravity of about 1.05-1.08;

such a kit wherein the percentages by weight of a), b), and c) in theprepolymer are respectively about 54%, about 36%, and about 10%; and

such a kit wherein the degassing aid in the curative is a siliconeemulsion and the catalyst is a mixture of triethylene diamine and2,3-dimethyltetrahydropyrimidine or bismuth neodecanoate.

GENERAL DESCRIPTION OF THE INVENTION

Component Descriptions

A. Prepolymer (P) Portion

The polyol components used in the prepolymer portion of the system arerepresented by polytetramethylene ether glycol or polyoxypropylene,polyoxyethylene or mixed polyoxypropylene/polyoxyethylene diols ortriols having molecular weights between 1000 and 6000 and anOH-functionality of about 2.0 to 3.0. Representative polyol componentsare:

Polytetramethylene ether glycol having a molecular weight between about1000 and 2800 and a functionality of about 2.0, such as PTMEG 2000 or anequivalent QO2000™ or Terathane 2000™. Other products which can be usedinclude PTMEG 1000, Great Lakes QO1000™, or DuPont Terathane 1000™.Further alternates include polyoxypropylene, polyoxyethylene or mixedpolyoxypropylene/polyoxyethylene diols with molecular weights from 1000to 2000 with functionalities of about 2.0. Examples of these alternatesinclude Arch Poly-G 20-56™, Arch Poly-G 55-112™, Bayer Multranol 3600™,Lyondell Acclaim 2220™, Dow Voranol 220-056™, and other polyols familiarto one skilled in the art such as:

Polyether triols having a molecular weight of about 4200 to 6000 and afunctionality of about 3.0 including low unsaturation polyethers, suchas Lyondell Acclaim 6320™. Other products which can be used include ArchPoly-G 85-28™, Arch Poly-G 30-28™, Arch Poly-L 385-29™, or Dow Voranol230-027™. Further alternates include polyoxypropylene, polyoxyethyleneor mixed polyoxypropylene/polyoxyethylene triols with molecular weightsof 4200 to 6000 and functionalities of about 3.0, which will be familiarto one skilled in the art.

The isocyanate component used in the prepolymer portion of the system isdiphenylmethane diisocyanate having a functionality of about 2.0-2.1.The prepolymer is based on pure methylene diphenylisocyanate (MDI) suchas Mondur M™ from Bayer or Rubinate 44™ from Huntsman or theirequivalent, or a previously prepared isocyanate-terminated prepolymerbased upon MDI and a polytetra-methylene ether glycol (PTMEG) of 1000 or2000 molecular weight (MW). Examples of these prepolymers include, butare not limited to, Mondur ME230™ from Bayer and Rubinate 1027™ fromHuntsman. Other isocyanate functional materials suitable for use includeuretonimine-modified methylene diphenylisocyanates commonly referred toas Mondur CD™ from Bayer, Rubinate 1680™ from Huntsman, or Isonate2143L™ from Dow and other equivalents. We have also evaluated and foundprepolymers based on methylene diphenylisocyanate reacted withpolyoxyethylene/polyoxypropylene diols of 1000 and 2000 MW to beacceptable. These materials are known by such tradenames as Isonate2181™ from Dow, Mondur MP210™ from Bayer, Rubinate 1209™ and Rubinate1790™ from Huntsman.

The prepolymer advantageously has a room-temperature viscosity of about1200 to 26000 cps. Especially when the percentage of residual NCO in theprepolymer is the preferred 11.5-13.5% NCO, a viscosity of 3500-5000 cpsis also preferred.

B. Curative (C) Portion

Polyol components used in the curative portion of the system arepolyoxypropylene, polyoxyethylene, or mixedpolyoxypropylene/polyoxyethylene diols or triols having molecularweights between 2000 and 6000 and OH-functionality of about 2.0 to 3.0.Representative polyol components are:

Commercially available low unsaturation polyoxyethylene terminatedpolyoxypropylene polyether triols and diols having a molecular weightsof about 2000 to 6000 and functionalities of between about 2.0 and 3.0,such as Lyondell Acclaim 6320™ and Acclaim 2220™. Other products whichcan be used include Arch Poly-L 385-29™, Poly-L 255-50™, Poly-G 85-28™,30-28™, 55-56™, Dow Voranol 220-028™ and 230-027™. Further alternatesinclude polyoxypropylene, polyoxyethylene or mixedpolyoxypropylene/polyoxyethylene diols and triols with molecular weightsfrom 2000 to 6000 and functionalities of about 2.0 to 3.0 which will befamiliar to one skilled in the art.

The curative portion advantageously has a room-temperature viscosity ofabout 300-50000 cps, especially 4000-5000 cps, and most advantageously aspecific gravity of about 1.02 to 1.15 and especially 1.05-1.08.

The crosslinker: The crosslinkers or chain extenders have molecularweights between about 50 and 250 and hydroxyl functionality of about2.0, and thus an equivalent weight of about 25 to 125, such as 1,4-BDOor MPDiol. Some examples are: butanediol, 2-methyl-1,3 propanediol,trimethylolpropane, glycerine, ethylene glycol based crosslinkers suchas DEG (diethylene glycol) and TEG (triethylene glycol), propylene basedcrosslinkers such as DPG (dipropylene glycol) or any combination ofthese components or other known crosslinkers familiar to one skilled inthe art.

The catalyst: Any effective urethane/urethane-inducing catalyst orcatalyst combination of the type which is normally used for urethaneproduction can be employed in an effective polyurethane-catalyzingamount. Tertiary amines and organometallic catalysts are especiallysuitable. Some examples of suitable catalysts are those containing tin,such as dibutyltindilaurate, bismuth, such as bismuth neodecanoate, orzinc, such as zinc octoate. Some examples of tertiary amines are:triethylene diamine, 2,3-dimethylhydropyrimidine, andN,N′-dimorpholinodiethyl ether. An effective amount of thepolyurethane-catalyzing catalyst to obtain the desired reaction profileand work life is employed. A metal catalyst works well for this product,but tertiary amines and catalyst combinations also provide acceptableproducts. Representative catalysts and catalyst combinations areutilized in the Examples which follow, and additional suitable catalystsare disclosed in our U.S. Pat. No. 5,554,713.

Prepolymer in the curative: A room-temperature liquid stable prepolymer(P) as defined earlier, namely, which is the reaction product of

a) methylene diphenylisocyanate or a prepolymer of methylenediphenylisocyanate and an about 500-1000 equivalent weight prepolymer ofMDI and polytetramethylene ether glycol orpolyoxypropylene/polyoxyethylene diol or triol having at least 21%residual NCO,

b) polytetramethylene ether glycol of about 500 to 1000 equivalentweight, and

c) a polyoxypropylene/polyoxyethylene triol or polyoxypropylene trial ofabout 1300 to 2000 equivalent weight,

the percentage by weight in the prepolymer (P) being about 32 to 72% of(a), about 52 to 22% of (b), and about 7 to 15% of (c), and thepercentage of residual NCO in the prepolymer (P) being about 6 to 18% byweight,

the prepolymer (P) having a viscosity at room temperature of about 1200to 26000 cps. Some examples of commercially available methylenediisocyanates are pure MDI and uretonimine-modified MDI. Amounts ofprepolymer in the curative are: 0-30, preferably 10-20, andadvantageously about 15 to 17% by weight of the curative.

Diluent: Any suitable urethane-compatible material including, but notlimited to alkyl phthalates such as dioctylphthalate,diisobutylphthalate, allyl benzyl phthalate; butyrates such as isobutylisobutyrate or 2,2,4-trimethyl-1,3 pentanediol diisobutyrate; phosphatessuch as triphenyl phosphate or tributyl phosphate; and adipates such asdioctyladipate. Further examples include dipropylene glycol dibenzoate,diethylene glycol dibenzoate, dimethyl glutarate, dimethyl adipate, anddimethyl succinate. The diluent can thus be any suitableurethane-compatible material including, but not limited to, phthalate,adipate, or phosphate-based diluents such as: diisobutylphthalate orisobutylbutyrate, good examples being Velsicol's Benzoflex™ 988SG orSolutia's Santicizer™ 160 or 261, or other materials familiar to oneskilled in the art. Amounts of diluent in the curative are: 0-30,preferably 5-15, and advantageously about 7 to 9% by weight of thecurative.

Degassing agent: Any degassing agent typically used in the industry toeliminate or reduce the formation of bubbles in polyurethane products.Typical materials containing silicone as surface tension depressingagents can be utilized. Some examples of these materials are: OSI's SAG47™, Furane Products' Airout™, and Ciba-Giegy's X-Air™. Other bubbleelimination agents known to users familiar with the art may also beemployed.

DETAILED DESCRIPTION OF THE INVENTION

The following Examples are given by way of illustration only, and arenot to be construed as limiting. All Curative Examples and UrethaneProduction Examples are carried out at room temperature (approximately77° F.).

Prepolymer Batch Processing Procedure

Examples of typical procedure for processing a prepolymer followed byother examples of weights and measures for alternate prepolymers follow.

PREPOLYMER EXAMPLE 1 (P1)

A laboratory blend of about one-half gallon of the prepolymer wasprepared by charging 812 grams of Rubinate 1027™ into a clean glassreactor. Dry nitrogen gas was used to blanket the liquid and mildagitation mixing was initiated via a mechanical mixing device. TheRubinate 1027™ is a commercial prepolymer produced from Rubinate 44™ anda polytetramethylene ether glycol of about 1000 molecular weight toyield a 26.5-27.5% NCO terminated-isocyanate of nominal 2.0functionality and an average molecular weight of 154. To this, 546.2grams of Terathane 2000™ is charged with constant agitation under anitrogen blanket. The Terathane 2000™ is a 2000 molecular weightpolytetramethylene ether glycol with a nominal functionality of 2.0. Tothis, 154 grams of Acclaim 6320™ is charged with constant agitationunder a nitrogen blanket. The Acclaim 6320 is a commercial lowunsaturation polyoxyethylene terminated polyoxypropylene polyether triolhaving a molecular weight of about 6000 and a functionality of about3.0. These components are allowed to mix to homogeneity for about 10 to15 minutes while the temperature of the liquid is monitored by aThermowatch™ temperature measuring and control device. The order ofaddition of components is not specific and some of the ingredients maybe blended prior to addition to the reactor. Apply a heating mantle tothe outside surface of the reaction flask and begin heating the flaskwith the aid of a variable autotransformer at a setting of 40%. Adjustthe setpoint of the Thermowatch™ to 177° F. Monitor the temperature ofthe reacting components until it reaches 177° F. and then begin timingfor prepolymer completion. About one hour after the reacting liquid hasachieved 177° F., sample the liquid for an NCO determination. Determinethe % NCO of the prepolymer following ASTM D2572. Continue sampling the% NCO approximately every hour until the % NCO between samples does notchange by more than 0.5% and within 0.2 points of the theoretical % NCO.At this point, degas the prepolymer under a vacuum of about 28 inches ofHg, turn off the heating mantle, agitator and nitrogen blanket andtransfer the prepolymer to an enclosed vessel under dry nitrogen. Thisprepolymer is allowed to cool to room temperature overnight and yields anominal 12.5% NCO prepolymer with a viscosity of 4100 cps and a specificgravity of 1.09.

Further examples of prepolymer processing utilize the same manufacturingprocedure with the specific differences prescribed in each example:

PREPOLYMER EXAMPLE 2 (P2)

A laboratory blend of about one-quart of the prepolymer was prepared bycharging 486.1 grams of Mondur CD™ into a clean glass reactor. Drynitrogen gas was used to blanket the liquid and mild agitation mixingwas initiated via a mechanical mixing device. The Mondur CD™ is acommercially available uretonimine-modified Mondur M™ to yield a roomtemperature liquid isocyanate with an NCO functionality of about 2.10and a molecular weight of about 142. To this, 406.2 grams of Terathane2000™ is charged with constant agitation under a nitrogen blanket. TheTerathane 2000™ is a 2000 molecular weight polytetramethylene etherglycol with a nominal functionality of 2.0. To this, 108 grams ofAcclaim 6320™ is charged with constant agitation under a nitrogenblanket. The Acclaim 6320™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether triol having amolecular weight of about 6000 and a functionality of about 3.0. Thisprepolymer is allowed to cool to room temperature overnight and yields anominal 12.5% NCO prepolymer.

PREPOLYMER EXAMPLE 3 (P3)

A laboratory blend of about one-gallon of the prepolymer was prepared bycharging 2861 grams of Rubinate™ 1027 into a clean glass reactor. Drynitrogen gas was used to blanket the liquid and mild agitation mixingwas initiated via a mechanical mixing device. The Rubinate™ 1027 is acommercial prepolymer produced from it Rubinate™ 44 and apolytetramethylene ether glycol of about 1000 molecular weight to yielda 27% NCO terminated-isocyanate of nominal 2.0 functionality and anaverage molecular weight of 154. To this, 888.4 grams of Terathane™ 2000is charged with constant agitation under a nitrogen blanket. TheTerathane™ 2000 is a 2000 molecular weight polytetramethylene etherglycol diol with a nominal functionality of 2.0. To this, 250.6 grams ofAcclaim™ 6320 is charged with constant agitation under a nitrogenblanket. The Acclaim™ 6320 is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether triol having amolecular weight of about 6000 and a functionality of about 3.0. Thesecomponents are allowed to mix to homogeneity for about 10 to 15 minuteswhile the temperature of the liquid is monitored by a Thermowatch™temperature measuring and control device. Apply a heating mantle to theoutside surface of the reaction flask and begin heating the flask withthe aid of a variable autotransformer at a setting of 40%. Adjust thesetpoint of the Thermowatch™ to 177° F. Monitor the temperature of thereacting components until it reaches 177° F. and then begin timing forprepolymer completion. About one hour after the reacting liquid hasachieved 177° F., sample the liquid for an NCO determination. Determinethe % NCO of the prepolymer following ASTM™ D2572. Continue sampling the% NCO approximately every one hour until the % NCO between samples doesnot change by more than 0.5% and within 0.2 points of the theoretical %NCO. At this point, degas the prepolymer under a vacuum of about 28inches of Hg, turn off the heating mantle, agitator and nitrogen blanketand transfer the prepolymer to an enclosed vessel under dry nitrogen.This prepolymer is allowed to cool to room temperature over night andyields a nominal 18% NCO prepolymer with a viscosity of 1280 cps and aspecific gravity of 1.119.

PREPOLYMER EXAMPLE 4 (P4)

A laboratory blend of about one-gallon of the prepolymer was prepared bycharging 1310.3 grams of Rubinate™ 1027 into a clean glass reactor. Drynitrogen gas was used to blanket the liquid and mild agitation mixingwas initiated via a mechanical mixing device. The Rubinate™ 1027 is acommercial prepolymer produced from Rubinate™ 44 and apolytetramethylene ether glycol of about 1000 molecular weight to yielda 27% NCO terminated-isocyanate of nominal 2.0 functionality and anaverage molecular weight of 154. To this, 2099.4 grams of Terathane™2000 is charged with constant agitation under a nitrogen blanket. TheTerathane™ 2000 is a 2000 molecular weight polytetramethylene etherglycol diol with a nominal functionality of 2.0. To this, 590.2 grams ofAcclaim™ 6320 is charged with constant agitation under a nitrogenblanket. The Acclaim™ 6320 is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether triol having amolecular weight of about 6000 and a functionality of about 3.0. Thesecomponents are allowed to mix to homogeneity for about 10 to 15 minuteswhile the temperature of the liquid is monitored by a Thermowatch™temperature measuring and control device. Apply a heating mantle to theoutside surface of the reaction flask and begin heating the flask withthe aid of a variable autotransformer at a setting of 40%. Adjust thesetpoint of the Thermowatch™ to 177° F. Monitor the temperature of thereacting components until it reaches 177° F. and then begin timing Asfor prepolymer completion. About one hour after the reacting liquid hasachieved 177° F., sample the liquid for an NCO determination. Determinethe % NCO of the prepolymer using ASTM™ D2572. Continue sampling the %NCO approximately every one hour until the % NCO between samples doesnot change by more than 0.5% and within 0.2 points of the theoretical %NCO. At this point, degas the prepolymer under a vacuum of about 28inches of Hg, turn off the heating mantle, agitator and nitrogen blanketand transfer the prepolymer to an enclosed vessel under dry nitrogen.This prepolymer is allowed to cool to room temperature over night andyields a nominal 6.0% NCO prepolymer with a viscosity of 26000 cps and aspecific gravity of 1.06.

PREPOLYMER EXAMPLE 5 (P5)

A laboratory blend of about one-half gallon of the prepolymer wasprepared by charging 911 grams of Mondur ME230™ into a clean glassreactor. Dry nitrogen gas was used to blanket the liquid and mildagitation mixing was initiated via a mechanical mixing device. TheMondur ME230™ is a commercial prepolymer produced from Mondur M™ and apolytetramethylene ether glycol of about 1000 molecular weight to yielda 23% NCO terminated-isocyanate of nominal 2.0 functionality and anaverage molecular weight of 182. To this, 436.3 grams of Terathane 2000™is charged with constant agitation under a nitrogen blanket. TheTerathane 2000™ is a 2000 molecular weight polytetramethylene etherglycol with a nominal functionality of 2.0. To this, 153.3 grams ofAcclaim 6320™ is charged with constant agitation under a 10 nitrogenblanket. The Acclaim 6320™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether trial having amolecular weight of about 6000 and a functionality of about 3.0. Thisprepolymer is allowed to cool to room temperature overnight and yields anominal 12.5% NCO prepolymer.

PREPOLYMER EXAMPLE 6 (P6)

A laboratory blend of about one-quart of the prepolymer was prepared bycharging 462.48 grams of pre-melted Mondur M™ into a clean glassreactor. Dry nitrogen gas was used to blanket the liquid and mildagitation mixing was initiated via a mechanical mixing device. TheMondur M™ is a pure methylene diphenylisocyanate (MDI) from BayerChemicals with a % NCO of 33.6, a molecular weight of 250, and afunctionality of 2.0. To this, 486 grams of Terathane 2000™ is chargedwith constant agitation under a nitrogen blanket. The Terathane 2000™ isa 2000 molecular weight polytetramethylene ether glycol with a nominalfunctionality of 2.0. To this, 114 grams of Acclaim 6320™ is chargedwith constant agitation under a nitrogen blanket. The Acclaim 6320™ is acommercial low unsaturation polyoxyethylene terminated polyoxypropylenepolyether triol having a molecular weight of about 6000 and afunctionality of about 3.0. This prepolymer is allowed to cool to roomtemperature overnight and yields a nominal 12.5% NCO prepolymer.

PREPOLYMER EXAMPLE 7 (P7)

A laboratory blend of about one-quart of the prepolymer was prepared bycharging 486.1 grams of Mondur CD™ into a clean glass reactor. Drynitrogen gas was used to blanket the liquid and mild agitation mixingwas initiated via a mechanical mixing device. The Mondur CD™ is acommercially available uretonimine-modified Mondur M™ to yield a roomtemperature liquid isocyanate with an NCO functionality of about 2.10and a molecular weight of about 142. To this, 406 grams of Acclaim 2220™is charged with constant agitation under a nitrogen blanket. The Acclaim2220™ is a 2000 molecular weight low unsaturationpolyoxypropylene/polyoxyethylene diol with a nominal functionality of2.0. To this, 108.1 grams of Acclaim 6320™ is charged with constantagitation under a nitrogen blanket. The Acclaim 6320™ is a commerciallow unsaturation polyoxyethylene terminated polyoxypropylene polyethertriol having a molecular weight of about 6000 and a functionality ofabout 3.0. This prepolymer is allowed to cool to room temperatureovernight and yields a nominal 12.5% NCO prepolymer.

PREPOLYMER EXAMPLE 8 (P8)

A laboratory blend of about one-quart of the prepolymer was prepared bycharging 537 grams of Rubinate 1027™ into a clean glass reactor. Drynitrogen gas was used to blanket the liquid and mild agitation mixingwas initiated via a mechanical mixing device. The Rubinate 1027™ is acommercial prepolymer produced from Rubinate 44™ and apolytetramethylene ether glycol of about 1000 molecular weight to yielda 29.5% NCO terminated-isocyanate of nominal 2.0 functionality and anaverage molecular weight of 154. To this, 361.1 grams of Terathane 2000™is charged with constant agitation under a nitrogen blanket. TheTerathane 2000™ is a 2000 molecular weight polytetramethylene etherglycol with a nominal functionality of 2.0. To this, 101.9 grams ofPoly-G 30-28™ is charged with constant agitation under a nitrogenblanket. The Poly-G 30-28™ is a 6000 molecular weight triol with anominal functionality of 3.0. This prepolymer is allowed to cool to roomtemperature overnight and yields a nominal 12.5% NCO prepolymer.

Curative Batch Processing Procedure

Examples of the procedure for processing a curative followed by examplesof weights and measures for alternate curatives follow.

CURATIVE EXAMPLE 1 (C1)

A laboratory bland of about one-gallon of the curative was prepared bycharging 2800 grams of Lyondell Acclaim 2220™ into a clean one-galloncontainer. The Acclaim 2220™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether diol having amolecular weight of about 2000 and a functionality of about 2.0. Tothis, 600 grams of Acclaim 6320™ is charged into the container. TheAcclaim 6320™ is a commercial low unsaturation polyoxyethyleneterminated polyoxypropylene polyether triol having a molecular weight ofabout 6000 and a functionality of about 3.0. To this, 600 grams of1,4-butanediol is charged into the container. The 1,4-butanediol is a 90molecular weight diol crosslinker with a nominal functionality of 2.0.To this, 0.2 gram of SAG 47™ (silicon emulsion) is added into thecontainer. Sag 47™ is a commercial degassing agent commonly used forbubble breaking and dissipation in the urethane industry. Finally, 0.18gram of bismuth neodecanoate 20% is charged into the container. Thebismuth neodecanoate is a polyurethane catalyst from Shepherd Chemicalsused in the industry for curing polyurethanes. These ingredients aremixed to homogeneity and degassed under about 28 inches of Hg vacuum.This curative blend is transferred to a closed container under anitrogen blanket and yields a viscosity of 550 cps.

CURATIVE EXAMPLE 2 (C2)

A laboratory blend of about one-gallon of the curative was prepared bycharging 2800 grams of Lyondell Acclaim 2220™ into a clean one-galloncontainer. The Acclaim 2220™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether diol having amolecular weight of about 2000 and a functionality of about 2.0. Tothis, 600 grams of Acclaim 6320™ is charged into the container. TheAcclaim 6320™ is a commercial low unsaturation polyoxyethyleneterminated polyoxypropylene polyether triol having a molecular weight ofabout 6000 and a functionality of about 3.0. To this, 600 grams of1,4-butanediol is charged into the container. The 1,4-butanediol is a 90molecular weight diol crosslinker with a nominal functionality of 2.0.To this, 0.2 gram of SAG 47™ is added into the container. Sag 47™ is acommercial degassing agent commonly used for bubble breaking anddissipation in the urethane industry. Finally, 2.60 grams of KE 9362™ ischarged into the container. The KE 9362™ is a proprietary polyurethanecatalyst comprising 2,3-dimethyltetrahydropyrimidine in atriethylenediamine and dipropylene glycol admixture from Rhein-Chemieused in the industry for curing polyurethanes. These ingredients aremixed to homogeneity and degassed under about 28 inches of Hg vacuum.This curative blend is transferred to a closed container under anitrogen blanket and yields a viscosity of 550 cps.

CURATIVE EXAMPLE 3 (C3)

A laboratory blend of about one-gallon of the curative was prepared bycharging 2800 grams of Lyondell Acclaim 2220™ into a clean one-galloncontainer. The Acclaim 2220™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether dial having amolecular weight of about 2000 and a functionality of about 2.0. Tothis, 600 grams of Acclaim 6320™ is charged into the container. TheAcclaim 6320™ is a commercial low unsaturation polyoxyethyleneterminated polyoxypropylene polyether triol having a molecular weight ofabout 6000 and a functionality of about 3.0. To this, 600 grams of1,4-butanediol is charged into the container. The 1,4-butanediol is a 90molecular weight dial crosslinker with a nominal functionality of 2.0.To this, 0.2 gram of SAG 47™ is added into the container. Sag 47™ is acommercial degassing agent commonly used for bubble breaking anddissipation in the urethane industry. Finally, 0.160 gram of BiCat 8™ ischarged into the container. The BiCat 8™ is a polyurethane catalyst fromShepherd Chemicals used in the industry for curing polyurethanes and iscomprised of an equal blend of bismuth neodecanoate and zincneodecanoate. These ingredients are mixed to homogeneity and degassedunder about 28 inches of Hg vacuum. This curative blend is transferredto a closed container under a nitrogen blanket and yields a viscosity of550 cps.

CURATIVE EXAMPLE 4 (C4)

A laboratory blend of about one-gallon of the curative was prepared bycharging 2800 grams of Lyondell Acclaim 2220™ into a clean one-galloncontainer. The Acclaim 2220™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether dial having amolecular weight of about 2000 and a functionality of about 2.0. Tothis, 600 grams of Acclaim 6320™ is charged into the container. TheAcclaim 6320™ is a commercial low unsaturation polyoxyethyleneterminated polyoxypropylene polyether triol having a molecular weight ofabout 6000 and a functionality of about 3.0. To this, 600 grams of1,4-butanediol is charged into the container. The 1,4-butanediol is a 90molecular weight diol crosslinker with a nominal functionality of 2.0.To this, 0.2 gram of SAG 47™ is added into the container. Sag 47™ is acommercial silicone emulsion degassing agent commonly used for bubblebreaking and dissipation in the urethane industry. Finally, 1.52 gramsof Toyocat F-10™ is charged into the container. The F-10™ is adimethylimidazole-containing polyurethane catalyst from Tosoh Chemicalsused in the industry for curing polyurethanes. These ingredients aremixed to homogeneity and degassed under about 28 inches of Hg vacuum.This curative blend is transferred to a closed container under anitrogen blanket and yields a viscosity of 550 cps.

CURATIVE EXAMPLE 5 (C5)

A laboratory blend of about one-gallon of the curative was prepared bycharging 2800 grams of Lyondell Acclaim 2220™ into a clean one-galloncontainer. The Acclaim 2220™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether diol having amolecular weight of about 2000 and a functionality of about 2.0. Tothis, 600 grams of Acclaim 6320™ is charged into the container. TheAcclaim 6320™ is a commercial low unsaturation polyoxyethyleneterminated polyoxypropylene polyether triol having a molecular weight ofabout 6000 and a functionality of about 3.0. To this, 600 grams of1,4-butanediol is charged into the container. The 1,4-butanediol is a 90molecular weight diol crosslinker with a nominal functionality of 2.0.To this, 0.2 gram of SAG 47™ is added into the container. Sag 47™ is acommercial silicone emulsion degassing agent commonly used for bubblebreaking and dissipation in the urethane industry. Finally, 0.80 gram ofTD-33™ is charged into the container. The TD-33™ is a triethylenediamine catalyst from Texaco or Focus Chemicals used in the industry forcuring polyurethanes. These ingredients are mixed to homogeneity anddegassed under about 28 inches of Hg vacuum. This curative blend istransferred to a closed container under a nitrogen blanket and yields aviscosity of 550 cps.

CURATIVE EXAMPLE 6 (C6)

A laboratory blend of about one-gallon of the curative was prepared bycharging 2800 grams of Lyondell Acclaim 2220™ into a clean one-galloncontainer. The Acclaim 2220™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether diol having amolecular weight of about 2000 and a functionality of about 2.0. Tothis, 600 grams of Acclaim 6320™ is charged into the container. TheAcclaim 6320™ is a commercial low unsaturation polyoxyethyleneterminated polyoxypropylene polyether triol having a molecular weight ofabout 6000 and a functionality of about 3.0. To this, 600 grams of1,4-butanediol is charged into the container. The 1,4-butanediol is a 90molecular weight diol crosslinker with a nominal functionality of 2.0.To this, 0.2 gram of SAG 47™ is added into the container. Sag 47™ is acommercial degassing agent commonly used for bubble breaking anddissipation in the urethane industry. Finally, 0.80 gram of SUL-4™ ischarged into the container. The SUL-4™ is a dibutyltin dilaurate metalcatalyst from CKWitco used in the industry for curing polyurethanes.These ingredients are mixed to homogeneity and degassed under about 28inches of Hg vacuum. This curative blend is transferred to a closedcontainer under a nitrogen blanket and yields a viscosity of 550 cps.

CURATIVE EXAMPLE 7 (C7)

A laboratory blend of about one-gallon of the curative was prepared bycharging 2800 grams of Lyondell Acclaim 2220™ into a clean one-galloncontainer. The Acclaim 2220™ is a commercial low unsaturationpolyoxyethylene terminated polyoxypropylene polyether diol having amolecular weight of about 2000 and a functionality of about 2.0. Tothis, 600 grams of Acclaim 6320™ is charged into the container. TheAcclaim 2220™ is a commercial low unsaturation polyoxyethyleneterminated polyoxypropylene polyether triol having a molecular weight ofabout 6000 and a functionality of about 3.0. To this, 600 grams of1,4-butanediol is charged into the container. The 1,4-butanediol is a 90molecular weight diol crosslinker with a nominal functionality of 2.0.To this, 0.2 gram of SAG 47™ is added into the container. Sag 47™ is acommercial degassing agent commonly used for bubble breaking anddissipation in the urethane industry. Finally, 0.32 gram of TD-33™ and1.0 gram of KE9362™ are charged into the container, The TD-33™ is atriethylene diamine catalyst from Texaco Chemicals and the KE 9362™ is aproprietary polyurethane catalyst comprising2,3-dimethyltetrahydropyrimidine in a triethylenediamine and dipropyleneglycol admixture from Rhein-Chemie used in the industry for curingpolyurethanes. These ingredients are mixed to homogeneity and degassedunder about 28 inches of Hg vacuum. This curative blend is transferredto a closed container under a nitrogen blanket and yields a viscosity of550 cps.

CURATIVE EXAMPLE 8 (C8)

A laboratory blend of about one-gallon of the curative was prepared bycharging 2800 grams of Arch Poly-G 55-56™ into a clean one-galloncontainer. The Poly-G 55-56™ is a commercial polyoxyethylene terminatedpolyoxypropylene polyether diol having a molecular weight of about 2000and a functionality of about 2.0. To this, 600 grams of Poly-G 85-29™ ischarged into the container. The Poly-G 85-29™ is a commercialpolyoxyethylene terminated polyoxypropylene polyether triol having amolecular weight of about 6000 and a functionality of about 3.0. Tothis, 600 grams of 1,4-butanediol is charged into the container. The1,4-butanediol is a 90 molecular weight diol crosslinker with a nominalfunctionality of 2.0. To this, 0.2 gram of SAG 47™ is added into thecontainer. Sag 47™ is a commercial degassing agent commonly used forbubble breaking and dissipation in the urethane industry. Finally, 0.32gram of TD-33™ and 1.0 gram of KE9362™ are charged into the container.The TD-33™ is a triethylene diamine catalyst from Texaco Chemicals andthe KE 9362™ is a proprietary polyurethane catalyst comprising2,3-dimethyltetrahydropyrimidine from Rhein-Chemie used in the industryfor curing polyurethanes. These ingredients to are mixed to homogeneityand degassed under about 28 inches of Hg vacuum. This curative blend istransferred to a closed container under a nitrogen blanket and yields aviscosity of 550 cps.

CURATIVE EXAMPLE 9 (C9)

A laboratory blend of about one-gallon was prepared by charging 2153.6grams of Acclaim™ 2220 into a clean one-gallon container. The Acclaim™2220 is a commercial low unsaturation polyoxyethylene-terminatedpolyoxypropylene polyether diol having a molecular weight of about 2000and a functionality of about 2.0. To this, 523.2 grams of Acclaim™ 6320is charged into the container. The Acclaim™ 6320 is a commercial lowunsaturation polyoxyethylene-terminated polyoxypropylene polyether triolhaving a molecular weight of about 6000 and a functionality of about3.0. To this, 400 grams of 1,4-butanediol is charged into the container.The 1,4-butanediol is a 90 molecular weight diol crosslinker with anominal functionality of 2.0. These ingredients are homogenized in thecontainer. To this, with constant agitation, 615.3 grams of theprepolymer, P1, is charged into the container. This mixture is broughtup to a temperature of 80° C. for about three hours to facilitatecompletion of reaction between the curative and the prepolymer. To this,307.6 grams of Santicizer™ 160 is added into the container. Santicizer™160 is a commercially available alkyl benzyl phthalate. To this, 0.2gram of SAG™ 47 is added into the container. SAG™ 47 is a commercialdegassing agent commonly used for bubble breaking and dissipation in theurethane industry. Finally, 0.2 gram of bismuth neodecanoate 20% isadded to the container. Bismuth neodecanoate 20% is a commercialcatalyst from Shepherd Chemicals. These ingredients are mixed tohomogeneity and degassed under about 28 inches of Hg vacuum. Thiscurative blend is transferred to a closed container under a nitrogenblanket and yields a viscosity of 3980 cps.

CURATIVE EXAMPLE 10 (C10)

A laboratory blend of about one-gallon was prepared by charging 1400grams of Acclaim™ 2220 into a clean one-gallon container. The Acclaim™2220 is a commercial low unsaturation polyoxyethylene-terminatedpolyoxypropylene polyether diol having a molecular weight of about 2000and a functionality of about 2.0. To this, 560 grams of Acclaim 6320 ischarged into the container. The Acclaim™ 6320 is a commercial lowunsaturation polyoxyethylene-terminated polyoxypropylene polyether triolhaving a molecular weight of about 6000 and a functionality of about3.0. To this, 840 grams of 1,4-butanediol is charged into the container.The 1,4-butanediol is a 90 molecular weight diol crosslinker with anominal functionality of 2.0. These ingredients are homogenized in thecontainer. To this, with constant agitation, 1200 grams of theprepolymer, P1, is charged into the container. This mixture is broughtup to a temperature of 80° C. for about three hours to facilitatecompletion of reaction between the curative and the prepolymer. To this,0.2 gram of SAG™ 47 is added into the container. SAG™ 47 is a commercialdegassing agent commonly used for bubble breaking and dissipation in theurethane industry. Finally, 0.2 gram of bismuth neodecanoate 20% isadded to the container. Bismuth neodecanoate 20% is a commercialurethane catalyst from Shepherd Chemicals. These ingredients are mixedto homogeneity and degassed under about 28 inches of Hg vacuum. Thiscurative blend is transferred to a closed container under a nitrogenblanket and yields a viscosity of 50,000 cps.

CURATIVE EXAMPLE 11 (C11)

A laboratory blend of about one-gallon was prepared by charging 2332.8grams of Acclaim™ 2220 into a clean one-gallon container. The Acclaim™2220 is a commercial low unsaturation polyoxyethylene-terminatedpolyoxypropylene polyether diol having a molecular weight of about 2000and a functionality of about 2.0. To this, 566.8 grams of Acclaim™ 6320is charged into the container. The Acclaim™ 6320 is a commercial lowunsaturation polyoxyethylene-terminated polyoxypropylene polyether triolhaving a molecular weight of about 6000 and a functionality of about3.0. To this, 433.2 grams of 1,4-butanediol is charged into thecontainer. The 1,4-butanediol is a 90 molecular weight diol crosslinkerwith a nominal functionality of 2.0. These ingredients are homogenizedin the container. To this, with constant agitation, 666.4 grams of theprepolymer, P1, is charged into the container. This mixture is broughtup to a temperature of 80° C. for about three hours to facilitatecompletion of reaction between the curative and the prepolymer. To this,0.2 gram of SAG™ 47 is added into the container. SAG™ 47 is a commercialdegassing agent commonly used for bubble breaking and dissipation in theurethane industry. Finally, 0.2 gram of bismuth neodecanoate 20% isadded to the container. Bismuth neodecanoate 20% is a commercialcatalyst from Shepherd Chemicals. These ingredients are mixed tohomogeneity and degassed under about 28 inches of Hg vacuum. Thiscurative blend is transferred to a closed container under a nitrogenblanket and yields a viscosity of 3100 cps.

CURATIVE EXAMPLE 12 (C12)

A laboratory blend of about one-gallon was prepared by charging 2153.6grams of Acclaim™ 2220 into a clean one-gallon container. The Acclaim™2220 is a commercial low unsaturation polyoxyethylene-terminatedpolyoxypropylene polyether diol having a molecular weight of about 2000and a functionality of about 2.0. To this, 523.2 grams of Acclaim™ 6320is charged into the container. The Acclaim™ 6320 is a commercial lowunsaturation polyoxyethylene-terminated polyoxypropylene polyether triolhaving a molecular weight of about 6000 and a functionality of about3.0. To this, 400 grams of 1,4-butanediol is charged into the container.The 1,4-butanediol is a 90 molecular weight diol crosslinker with anominal functionality of 2.0. These ingredients are homogenized in thecontainer. To this, with constant agitation, 615.2 grams of theprepolymer, P4, is charged into the container. This mixture is broughtup to a temperature of 80° C. for about three hours to facilitatecompletion of reaction between the curative and the prepolymer. To this,307.6 grams of Santicizer™ 160 is added into the container. Santicizer™160 is a commercially available alkyl benzyl phthalate. To this, 0.2gram of SAG™ 47 is added into the container. SAG™ 47 is a commercialdegassing agent commonly used for bubble breaking and dissipation in theurethane industry. Finally, 0.2 gram of bismuth neodecanoate 20% isadded to the container. Bismuth neodecanoate 20% is a commercialcatalyst from Shepherd Chemicals. These ingredients are mixed tohomogeneity and degassed under about 28 inches of Hg vacuum. Thiscurative blend is transferred to a closed container under a nitrogenblanket and yields a viscosity of 26000 cps.

CURATIVE EXAMPLE 13 (C13)

A laboratory blend of about one-gallon was prepared by charging 2153.6grams of Acclaim™ 2220 into a clean one-gallon container. The Acclaim™2220 is a commercial low unsaturation polyoxyethylene-terminatedpolyoxypropylene polyether diol having a molecular weight of about 2000and a functionality of about 2.0. To this, 523.2 grams of Acclaim™ 6320is charged into the container. The Acclaim™ 6320 is a commercial lowunsaturation polyoxyethylene-terminated polyoxypropylene polyether triolhaving a molecular weight of about 6000 and a functionality of about3.0. To this, 400 grams of 1,4-butanediol is charged into the container.The 1,4-butanediol is a 90 molecular weight diol crosslinker with anominal functionality of 2.0. These ingredients are homogenized in thecontainer. To this, with constant agitation, 615.2 grams of theprepolymer, P3, is charged into the container. This mixture is broughtup to a temperature of 80° C. for about three hours to facilitatecompletion of reaction between the curative and the prepolymer. To this,307.6 grams of Santicizer™ 160 is added into the container. Santicizer™160 is a commercially available alkyl benzyl phthalate. To this, 0.2gram of SAG™ 47 is added into the container. SAG™ 47 is a commercialdegassing agent commonly used for bubble breaking and dissipation in theurethane industry. Finally, 0.2 gram of bismuth neodecanoate 20% isadded to the container. Bismuth neodecanoate 20% is a commercialcatalyst from Shepherd Chemicals. These ingredients are mixed tohomogeneity and degassed under about 28 inches of Hg vacuum. ThisCurative blend is transferred to a closed container under a nitrogenblanket and yields a viscosity of 2160 cps.

Elastomer Casting Procedures

An example of the procedure for casting polyurethane products from theprepolymer and curative components follows, and is given as an exampleof a general casting procedure with variations possible for thoseknowledgeable in the art.

The prepolymer is weighed into a suitable container and degassed underabout 28 inches of Hg vacuum to remove dissolved gases. Based upon theweight of prepolymer, the curative weight is calculated and the curativedegassed under about 28 inches of Hg vacuum. The curative weight iscalculated to provide approximately stoichiometric equivalents ofprepolymer and curative, preferably not more than a 13% excess and mostpreferably a 2 to 7 percent stoichiometric excess of the prepolymer.This ratio of prepolymer equivalents to curative equivalents is referredto as the index and the index is generally 1.0 to 1.13/1.0 and mostpreferably 1.02 through 1.07/1.0. The curative is then added to theprepolymer and mixed to homogeneity at room temperature (approximately77° F.). The mixture is then degassed under about 28 inches of Hg vacuumto remove air entrapped during the mixing procedure. The degassedmixture is then introduced into the mold by slowly pouring the reactingliquid down the side of the mold to the desired fill point. In the caseof test molds, a dividing plate is slid into the mold to produce twotest panels of 0.080 thickness. The material is allowed to react to apoint where it can be removed from the mold without undue stress on thefinished urethane product. This test plaque is then allowed to set atroom temperature for a minimum of seven-days from the time it was pouredinto the mold. At this time, test parts are cut from the 0.080 inchthick panels by standardized cutters, tested as per the respective ASTMtest procedures, and the results recorded.

In the Table which follows, the viscosity is at room temperature in cpsand the gel time is at a temperature of 25° C.

Results and Properties of Examples the results and physical propertiesof the products of the examples follow Example A Example B Example CExample D Example E Example F Example G Example H Prepolymer Example P1P2 P1 P1 P5 P6 P7 P1 % NCO 12.64 12.47 12.8 12.8 12.43 12.52 12.52 12.64Liquid @ Room Temperature Yes Yes Yes Yes Yes Yes Yes Yes Liquid StableYes Yes Yes Yes Yes Yes Yes Yes Curative Example C7 C7 C13 C12 C7 C7 C7C1 Viscosity 550 550 2160 26000 550 550 550 550 Liquid Stable Yes YesYes Yes Yes Yes Yes Yes Mix Ratio Curative per 100 69.8 68.8 129.48109.12 68.6 72.6 69.1 70.5 Prepolymer Tensile in psi (ASTM D-412) 22812170 1339 1589 1673 1848.2 1846 2150.6 Elongation in % (ASTM D-412)683.5 373 401 458 661.2 539.1 696.9 535.3 Die-C Tear in pll (ASTM D-624)276 281 289 246 377.4 219 250 285.4 Trouser Tear in pll (ASTM D-1938)65.2 54 54 41 95.1 55.3 74 44.7 Shore A Hardness (ASTM D-2240) 84 83 8282 79 73 82 85 % Rebound (ASTM D-2632) 58 53 53 59 60 46 55 57 Gel Time26 min 25 min 22 min 18 min 30 min 32 min 28 min 28 min Example IExample J Example K Example L Example M Example N Example O Example PExample Q Prepolymer Example P1 P1 P1 P1 P1 P1 P1 P1 P1 % NCO 12.6412.64 12.64 12.64 12.64 12.52 12.8 12.8 12.8 Liquid @ Room Yes Yes YesYes Yes Yes Yes Yes Yes Temperature Liquid Stable Yes Yes Yes Yes YesYes Yes Yes Yes Curative Example C2 C3 C4 C5 C6 C8 C9 C10 C11 Viscosity550 550 550 550 550 550 3980 50,000 3,100 Liquid Stable Yes Yes Yes YesYes Yes Yes Yes Yes Mix Ratio Curative 70.5 70.5 70.5 70.5 70.5 69.5 12567.8 66.83 per 100 Prepolymer Tensile in psi 2700 2082.4 2286 1764.42163.4 2146 1400 2208 1643 (ASTM D-412) Elongation in % 512.3 592.4687.7 629.3 515.7 601.6 535 519 430 (ASTM D-412) Die-C Tear in pll 302.2324.9 255.5 278.3 240.7 273.5 223 342 261 (ASTM D-624) Trouser Tear inpll 80.2 54.5 66.2 65 50.3 79.2 47.5 89 50 (ASTM D-1938) Shore AHardness 84 86 84 84 86 83 80 94 85 (ASTM D-2240) % Rebound 55 57 57 5558 54 56 54 54 (ASTM D-2632) Gel Time 21 min 27 min 28 min 28 min 27 min26 min 27 min 30 min 29 min

Cured Polyurethane Product

The following is an example of a typical method of pour-in-placepolyurethane elastomer production.

Verify all individual factors involved in the pour prior to proceedingwith the fill process. Check the prepolymer for % NCO, componenttemperatures, adequate degassing of the individual components, moldtemperature, and the mix capabilities of the equipment. Using theselected prepolymer and curative, calculate and verify the correct ratioof components to be used. Verify that the mold is assembled properlywith all inserts and integral parts properly treated and correctlypositioned and attached.

If using a metering machine, measure timed shots of the individualcomponents and adjust the equipment to meter the correct componentratio. Measure and record the ratio several times at the process speedsand temperatures under which the elastomer will be poured to ensurecorrect processing. Verify that the machine has sufficient material forthe part(s) to be poured and actuate the machine. Pour a small sample toverify thorough mixing, freedom from air and moisture contamination, andthe correct gel time. Ensure that the machine has sufficient flushmaterial. Arrange the molds to be poured in a manner to facilitate theproduction of the parts for ease and efficiency. Make any adjustmentsnecessary to achieve the desired processing conditions and begin fillingthe molds in a manner to minimize the possibility of air occlusion. Fillthe molds to the correct fill level.

If hand pouring, verify the mixing equipment and the scale accuracybefore mixing. Arrange the molds to be poured in a manner to facilitatethe production of the parts for ease and efficiency. Weigh out thecorrect component quantities and blend them thoroughly while introducingas little air as possible into the product. If time permits, de-gas theblended system at 28-30 in. of Hg while watching to minimize thepotential for difficulties caused by overflow of the material when foamis produced. Remove the degassed system and fill the mold(s) in a mannerto minimize the possibility of air occlusion. Fill the molds to thecorrect fill level.

This procedure can be followed for room- or ambient-temperatureproduction of numerous types of polyurethane elastomeric products fromthe prepolymer and curative components of the present invention,including industrial tires, vibratory bowl linings, sprockets andcouplings, gaskets, skateboard wheels, and a variety of otherapplications requiring a high-performance polyurethane elastomer.

For purposes of customer/user convenience, the selected prepolymer andits precalculated complementary curative may advantageously beseparately packaged, but sold together as a single unit or kit.

It is to be understood that the present invention is not to be limitedto the exact details of operation, or to the exact compounds,compositions, methods, procedures, or embodiments shown and described,as various modifications and equivalents will be apparent to one skilledin the art, wherefore the present invention is to be limited only by thefull scope which can be legally accorded to the appended claims.

What is claimed is:
 1. A urethane elastomer which is the reactionproduct of a prepolymer (P) having a room temperature viscosity of about1200 to 26000 cps and which is the reaction product of a) methylenediphenylisocyanate or a prepolymer of methylene diphenylisocyanate andan about 500-1000 equivalent weight polytetramethylene ether glycol orpolyoxypropylene/polyoxyethylene diol or triol having at least 21%residual NCO, b) polytetramethylene ether glycol of about 500 to 1000equivalent weight, and c) a polyoxypropylene/polyoxyethylene triol orpolyoxypropylene triol of about 1300 to 2000 equivalent weight, thepercentage weight/weight in the prepolymer (P) being about 32 to 72% of(a), about 52 to 22% of (b), and about 6 to 15% of (c), and thepercentage of residual NCO in the prepolymer (P) being about 6 to 18% byweight, which is curable at room temperature with an approximatelystoichiometric equivalent of a liquid curative consisting essentially ofthe following components: (1) a polyoxypropylene/-polyoxyethylene diolof about 1000 to 2000 equivalent weight, (2) apolyoxypropylene/-polyoxyethylene triol of about 1300 to 2000 equivalentweight, (3) a chain extender having an equivalent weight of about 25 to125, (4) a room-temperature liquid stable prepolymer (P) having a 6 to18% residual NCO, (5) a diluent, (6) a degassing aid, and (7) a urethanecatalyst, the relative weight % amounts being respectively 30-90%,3-20%, 5-30%, 0-30%, 0-15%, 0.001-0.05%, and 0.006-0.5%, based on theweight of the liquid curative.
 2. The urethane elastomer of claim 1,wherein the percentage of residual NCO in the prepolymer (P) is about11.5-13.5% weight/weight and the liquid curative has a room-temperatureviscosity of about 550-50000 cps, and which results in a cured uretnaneelastomer having the following properties after mixing and curing forseven days at room temperature: Tensile strength (ASTM Method D-412)about 1300-2700 psi Elongation (ASTM Method D-412) about 250-700% Die CTear (ASTM Method D-695) about 140-400 pli Split Tear (ASTM MethodD-1938) about 20-100 pli Rebound (ASTM Method D-2632) about 45-65% ShoreA Hardness (ASTM Method D-2240) about 70-95 Gel time (25° C.) about14-40 min..


3. The urethane elastomer of claim 2 wherein the percentage of residualNCO is about 11.5-13.5% by weight, the prepolymer (P) has a roomtemperature viscosity of about 3500 to 5000 cps, and the amounts of (4)and (5) in the curative are respectively 10-20 and 5-15% weight/weight.4. The urethane elastomer of claim 2 wherein the amounts of (4) and (5)in the curative are respectively 10-20 and 5-15% weight/weight.
 5. Theurethane elastomer of claim 2 wherein the prepolymer (P) is present inan up to about 13% stoichiometric excess with respect to the curative.6. The urethane elastomer of claim 5 wherein the prepolymer (P) ispresent in about a 2 to 7% stoichiometric excess with respect to thecurative.
 7. The urethane elastomer of claim 1 wherein the prepolymer(P) consists of about 54%, about 36%, and about 10% percentweight/weight of the stable prepolymer (P) ingredients a), b), and c)respectively.
 8. The urethane elastomer of claim 7 which is cured withan approximately stoichiometric equivalent of a curative consistingessentially of (1) a polyoxypropylene/-polyoxyethylene diol of about1000 to 2000 equivalent weight, (2) a polyoxypropylene/-polyoxyethylenetriol of about 1300 to 2000 equivalent weight, (3) a chain extenderhaving an equivalent weight of about 25 to 125, (4) a room-temperatureliquid stable prepolymer (P) having a 11.5 to 13.5% residual NCO, (5) adiluent, (6) a degassing aid, and (7) a urethane catalyst, the relativeamounts weight/weight being respectively approximately 54%, 13%, 10%,15%, 8%, 0.005% and 0.006%.
 9. The urethane elastomer of claim 8 whereinthe curative has a viscosity at room temperature of about 3000-5000 cpsand a specific gravity of about 1.05-1.08.
 10. The urethane elastomer ofclaim 9 wherein the prepolymer (P) is present in an up to about 13%stoichiometric excess with respect to the curative.
 11. The urethaneelastomer of claim 10 wherein the prepolymer (P) is present in about a 2to 7% stoichiometric excess with respect to the curative.
 12. Theurethane elastomer of claim 11 wherein the properties after mixing andcuring for seven days at room temperature are as follows: Tensilestrength (ASTM Method D-412) about 1550 psi Elongation (ASTM MethodD-412) about 500% Die C Tear (ASTM Method D-695) about 250 pli SplitTear (ASTM Method D-1938) about 45 pli Rebound (ASTM Method D-2632)about 55% Shore A Hardness (ASTM Method D-2240) about 80 Gel time (25°C.) about 20-30 min..


13. The urethane elastomer of claim 12 wherein the degassing aid is asilicone emulsion.
 14. The urethane elastomer of claim 12 wherein thecatalyst is a mixture of triethylene diamine and2,3-dimethyltetrahydropyrimidine or bismuth neodecanoate.
 15. Theurethane elastomer of claim 12 wherein the degassing aid is a siliconeemulsion and the catalyst is a mixture of triethylene diamine and2,3-dimethyltetrahydropyrimidine or bismuth neodecanoate.
 16. A kitcomprising a separately packaged prepolymer (P) of claim 1, and aseparately packaged liquid curative of claim
 1. 17. The kit of claim 16wherein the separately packaged liquid curative has a viscosity at roomtemperature of about 300-50000 cps and a specific gravity of about1.02-1.15.
 18. The kit of claim 16 wherein the percentage of residualNCO in the prepolymer (P) is about 11.5-13.5% weight/weight and whereinthe prepolymer (P) has a room temperature viscosity of about 3500 to50000 cps.
 19. The kit of claim 18 wherein the amounts of (4) and (5) inthe separately packaged liquid curative are respectively 10-20 and 5-15%weight/weight.
 20. The kit of claim 18 wherein the separately packagedliquid curative consists essentially of the stated components in thefollowing approximate percentages: 54%, 13%, 10%, 15%, 8%, 0.005%, and0.006% weight/weight in the curative respectively and has a viscosity atroom temperature of about 3000 to 5000 cps and a specific gravity ofabout 1.05-1.08.
 21. The kit of claim 20 wherein the percentagesweight/weight of a), b), and c) in the prepolymer (P) are respectivelyabout 54%, about 36%, and about 10%.
 22. The kit of claim 20 wherein thedegassing aid in the separately packaged liquid curative is a siliconeemulsion and the catalyst is a mixture of triethylene diamine and2,3-dimethyltetrahydropyrimidine or bismuth neodecanoate.